//---------------
if you get missing functions or something, in generated_api_registration.cc
then you need to find an *.idl file
for example

gen/extensions/browser/api/generated_api_registration.cc:101:30: error: unknown type name 'SerialGetDevicesFunction'; did you mean 'HidGetDevicesFunction'?
  registry->RegisterFunction<SerialGetDevicesFunction>();
                               ^~~~~~~~~~~~~~~~~~~~~~~~

was a file extensions/common/api/serial.idl
a function named: getDevices under interface Functions in namespace serial

//---------------

